Science fiction has envisaged the possibility of everything from kind, wise,
and even cute extraterrestrials, like E.T., to utterly malicious, scheming
monsters, like Giger's Alien. On balance, ever since H. G. Wells unleashed
his marauding Martians, the fictional creatures from "out there" have tended
to be of the usurping, death-ray variety - not surprisingly, since this
makes for a more compelling plot. But if we do encounter other
intelligences among the stars, will they in reality prove to be friendly or
hostile?

A poll conducted by the Marist Institute in 1998 suggested that 86% of
Americans who think there is life on other planets believe it will be
friendly. Similar optimism has been expressed by many prominent figures in
SETI, including Frank Drake, Philip Morrison, and Carl Sagan. An argument
in favor of alien beneficence is that any race which has managed to survive
the kind of global crises currently facing humanity (and which presumably
confront all technological species at some stage in their development) is
likely to have resolved the sources of conflict we still have on Earth.
Morrison, for instance, doubted that advanced societies "crush out any
competitive form of intelligence, especially when there is clearly no
danger." Similarly, Arthur C. Clarke has stated that: "As our own species
is in the process of proving, one cannot have superior science and inferior
morals. The combination is unstable and self-destroying."

However, there can be no assurance on this point. After all, human beings
appear to have made little progress, over the past two millennia or so,
toward eliminating or controlling their aggressive tendencies. And there is
no reason to suppose we shall change much in this respect over the next few
centuries, during which time we may well develop the means of reaching the
stars. Those who are pessimistic about the general nature of
extraterrestrials argue that Darwinism, and its fundamental tenet "survival
of the fittest", virtually guarantees that any advanced species will be
potentially dangerous. Michael Archer, professor of biology at the
University of New South Wales, Australia, has put it this way: "Any creature
we contact will also have had to claw its way up the evolutionary ladder and
will be every bit as nasty as we are. It will likely be an extremely
adaptable, extremely aggressive super-predator."

Perhaps the most reasonable assumption, in the absence of any data, is that,
just as in our own case, the potential for good and evil will exist in every
intelligent extraterrestrial race. Civilization is unthinkable without some
measure of compassion, and yet how could a species that had emerged
successfully after several billion years of live-and-let-die biological
competition not also possess a ruthless streak? The question is surely not
whether any advanced race we may meet among the stars is capable of
aggression - it certainly will be unless it has genetically or otherwise
altered itself to be purely pacific - but whether it has learned to override
its more basic instincts. Bear in mind, too, the variation in character
that can exist between individuals within a species. Will the first
representative of an alien race that we encounter be a Hitler or a Gandhi?